Along with Roissypôle, the town hall in Lillebonne (Seine-Maritime) is one of the most emblematic buildings of Claude Parent’ career. This town hall, with its soaring lines intentionally differentiating the building from the urban context, attests to the architect’s enduring commitment to his theories and purpose. He designed this building to serve as a “signal in the city, as a symbolic and monumental sign of its role and its function.” And if the purpose remains similar, the aesthetic is quite different from the many town halls where architectural classical styles have most often been chosen. The former town hall built in 1837, and later enlarged numerous times, echoed the architecture of Roman theaters employing a vocabulary from classical antiquity on the façade which resulted in the nickname of “White House.” This building at the heart of municipal governance communicates with the old center of the town while also opening onto the main thoroughfare of modern times (east-west diagonal) that links centers of urban growth. Steered by implicit movement, the building (4,436 m²) takes the form of a ship’s prow emerging above the neighborhood roofline. The floor plan distributes interior spaces along an entry corridor (ground floor +1); which passes through the oblong form of the whole like an arrow. This “fracture” in the plan shows up in the earliest sketches and served as a guide for the various stages of the project.